I just found out about it. Open Source messaging. It seems intriguing although I'm not sure I would have much to do with it. I honestly can't find too much information about it except for the website and a few YouTube videos. I was just curious if anyone has had experience with it.
I did! Don't expect too much stability out of it, but I was surprised to say that the latest version worked pretty stable and nicely for me. I can definitely recommend it.